When pipes carrying a flowable material (e.g., liquid, gas, or semi-solid sludge) age and deteriorate, they begin to leak and must be rehabilitated. This rehabilitation is important for pipes such as buried sewer and water pipes, as well as for vent pipes. Traditionally, sewer and water pipes were dug up and replaced, which is extremely costly and time-consuming. To avoid this, trenchless pipeline rehabilitation techniques have been developed. These techniques involve relining the pipes from one dug-up access location, without digging an access/replacement trench along the entire length of the pipe. Typical relining techniques use a cured-in-place PVC reliner to form a sealed pipe-within-a-pipe.
But when relining mainline pipes, oftentimes connections (junctions) for laterals (branch pipes) become blocked (completely closed up or partially constricted) by the material relining the main pipe, thereby completely or partially restricting flow into the laterals of the pipe system. Such reliner blockages are typically cut out using lateral reinstatement cutters. Lateral reinstatement cutters are cutting tools that are inserted into mainline pipes to remotely cut out reliner blockages at lateral connection points from within the relined pipe. A conventional lateral reinstatement cutter is disclosed by U.S. Pat. No. 8,015,695, which is hereby incorporated by reference herein.
While conventional lateral reinstatement cutters are operable to re-open blocked laterals, they have their drawbacks. One such drawback is that for use, a camera must be inserted into the pipe at a separate/second access location (e.g., a dug-out pit) from the first access location where the reliner and cutter equipment is inserted. The camera is needed to remotely observe the position and function of the cutter so it can be controlled properly. But this two-point entry method can require significant additional time and effort to locate and access (e.g., dig up) the second access location. This is particularly problematic for vertical stack pipes, as accessing the second lower access location can be difficult, and the shavings from the cutting process typically fall onto the camera lens obscuring the image of the cutter. In addition, conventional lateral reinstatement cutters do not fit into two- or three-inch pipes, and are only usable to reline larger-diameter pipes. Because of such drawbacks, the most time-consuming and difficult task in many pipe relining applications is reinstating the lateral connections.
Accordingly, it can be seen that needs exist for improvements to lateral reinstatement cutters and methods of use thereof to make it quicker and easier to reinstate lateral connections during pipe relining work. It is to the provision of solutions to these and other problems that the present invention is primarily directed.